This build is designed for solo overland, but I regularly take it through vet dungeons as DPS. It was inspired by Hack the Minotaur's Blood Frenzy build (https://www.hacktheminotaur.com/builds/eso-magicka-nightblade-solo-vampire-pve-build-blood-frenzy), but with some personal modifications. Due to the use of Sated Fury, this build does take a substantial amount of time to get used to. However, once the timing of the abilities is down it is a very effective and fun.

Gear Set 1 - Mother's Sorrow. This build is very heavily focused on critical damage, and this set is needed in order to proc as many criticals as possible. The only alternative I can think of is Treasure Hunter, but Mother's Sorrow with Major Prophecy from a potion provides more spell crit, which is why I have not tested Treasure Hunter.

Gear Set 2 - Hollowfang Thirst. This may at first seem like an unusual choice for a DPS build. Do remember that this a solo build first with good DPS capabilities. The reason I chose it is that it really helps with sustain of the two main resource pools. With Sated Fury and Blood for Blood, your health can really drain fast. While it seems small, that boost to healing that an almost constant Minor Vitality gives makes has allowed me to keep Sated Fury on longer between refreshes. Some alternatives:
Crafty Alfiq's - Much larger starting Magicka pool, but with a significant drop in crit chance and no assistance with restoring health.
Law of Julianos / War Maidens - Both very similar to Hollowfang Thirst with the 5 piece being different. If you are looking for outright damage, my suggestion is War Maiden as the only non-Magicka damage ability, Elemental Blockade, is there mostly to proc a weapon damage enchantment. However, I found the lack of the added healing decrease how long I could keep Sated Fury up by about 5 seconds.
Bahraha's Curse - A set I was considering but ultimately did not test. The extra health, damage, and healing looked impressive, but with the same lack of crit chance as Alfiq's and lack of Magicka sustain.

Monster Set - Iceheart. Boosted crit chance with extra damage and a nice damage shield.

Main Bar Weapon - Piercing, Hardened Enchant.
Back Bar Weapon - Infused, Weapon Enchant.
Jewelry - One reduce spell cost and two boost spell damage enchantments. Arcane Trait.
Potions - Essence of Spell Crit, for health and Magicka restore and Major Prophecy.

Always keep Siphoning Attacks, Merciless Resolve, and Elemental Blockade up. Have Sated Fury on as much as possible, but it takes some practice knowing when to turn it on and off (watch out for cc's). Most of the time you want to be at melee with Blood for Blood as the spammable, or Sap Essence for mobs. Before beginning several hits with Blood for Blood, hit Sap Essence for Major Sorcery and Swallow Soul for the heal. For some dungeon fights, I find it easier to stay at range with Swallow Soul as the spammable. Having Impale on the main bar is a personal preference, though likely more useful in group play. The major alternative for that slot is Lotus Fan, if you really prefer the gap closer. Most of the time, I use my ultimate on Soul Harvest for the extra damage, which can be particularly nice if triggered as part of the execution.